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Large-scale molecular dynamics (MD) simulations of freely decaying turbulence in three-dimensional space are reported. Fluid components are defined from the microscopic states by eliminating thermal components from the coarse-grained fields. The energy spectrum of the fluid components is observed to scale reasonably well according to Kolmogorov scaling determined from the energy dissipation rate and the viscosity of the fluid, even though the Kolmogorov length is of the order of the molecular scale.

The paper proposes an amendment to the relativistic continuum mechanics which introduces the relationship between density tensors and the curvature of spacetime. The resulting formulation of a symmetric stress–energy tensor for a system with an electromagnetic field leads to the solution of Einstein Field Equations indicating a relationship between the electromagnetic field tensor and the metric tensor. In this EFE solution, the cosmological constant is related to the invariant of the electromagnetic field tensor, and additional pulls appear, dependent on the vacuum energy contained in the system. In flat Minkowski spacetime, the vanishing four-divergence of the proposed stress–energy tensor expresses relativistic Cauchy’s momentum equation, leading to the emergence of force densities which can be developed and parameterized to obtain known interactions. Transformation equations were also obtained between spacetime with fields and forces, and a curved spacetime reproducing the motion resulting from the fields under consideration, which allows for the extension of the solution with new fields.

Oil spill accidents occur in marine traffic accidents. Once the accidents happen, oil spill will drift and diffuse on the ocean as impacted by wind and tidal current, which has considerably impacted the work on wharfs and their surrounding environment. This study aimed to investigate the effect of wind, ocean current and tides on oil spill movement for the building of the drift and weathering models of oil particles to predict and assess the risks of oil spill on the ocean. In these models, the oil film drift algorithm considers the joint action of wind, ocean current, wave and density flow on oil spill. In this study, the fluid dynamic model was adopted to determine the drift motion generated by the tidal field, and the diffusion process was calculated with the random walk method. In addition, the random movement model of oil particles was employed for simulating the transport and weathering of the oil spill, as an attempt to simulate marine oil spill. Furthermore, the Ningbo port was taken as an example to obtain the numerical sum of the flow field obtained by the simulation, which can guide the prediction of oil spill risks near ports.

We discuss the most general Finsler spacetime geometry obeying the cosmological symmetry group SO(4). On this background geometry we derive the equations of motion for the most general kinetic fluid obeying the same cosmological symmetry. For this purpose we propose a set of coordinates on the tangent bundle of the spacetime manifold which greatly simplifies the cosmological symmetry generators.